Current controlling apparatus



Nov. 23, 1937. H. E. YOUNG 2,099,714

CURRENT CONTROLLING APPARATUS Filed March 1, 1933 2 Sheets-Sheet 1 ZEzverzZarx 2 Sheets-Sheet 2 v H. E; YOUNG J CURRENT CONTROLLINCLAPPARATUS Fil ed March 1, 1933 A Y I 355? fivenz ar 27 001% Patented Nov. 23, 1937 UNITED STATES PATENT OFFICE Applicatz i i l t ifrczz j ilg ezfl :1: 659,18h

3Claims.

This invention relates toimprovements in current controlling apparatus and, more especially, such apparatus embodying a grid-controlled arc rectifying tube.

In my application, Serial No. 618,369, filed June 20, 1932, Patent 2,071,446 of February 23, 1937, I have disclosed the broad idea 01' maintaining constant current in a load circuit such as a series lamp circuit. By shifting the phase of grid excitation of a pair of rectifying tubes responsive to current flow in the load or work circuit, the eflective flow of current per umt of time is maintained constant for all variations of load resistance from maximum for which the circuit is designed to substantially short circuit value. In that system both lobes of the alternating current wave are transmitted through the load circuit. I have discovered that a series lamp circuit need not employ so-called full wave rectification, but will operate satisfactorily with full illumination upon half wave rectification of commercial sixty cycle current, and at a substantial reduction in energy expended for a given amount of illumination. Since the eflective current flow per unit of time according to the present invention is made up of impulses of a irequency the same as the frequency of the impressed alternating current, whereas according to the system of said prior application, the impulses are of a frequency double that of the impressed frequency, it is to he observed that the impulses of current flow according to the present invention are of greater amplitude, i: a, high-- or value of instantaneous current flow. The re suit is a greater instantaneous heating oi the filament in the case of a lamp or greater instantanecus magnetic effect in case or electroma netic apparatus. This oilers definiteadvantages for certain classes of service.

The invention is capable or many applications. In order to illustrate one, I have shown 8,P13&= rains for controlling the direct current delivered by the tube, for example, to aseries street lighting system, in which the effective current flow per unit of time is automatically maintainedsuh stantially constant regardless of variations in the load. In such systems it is customary to provide automatic short circuits (not shown) for the lamps so that as one burns out, it is automatically short circuited. It will be seen, therefore, that the resistance in the line will vary from time to time, depending upon the number of lamps in commission. By the use of my inven tion. the effective current flow delivered per unit of time will be maintained substantially constant, regardless of variations of resistance irom maximum value for which the system is designed to substantially short circuit value;

In general, it may be stated that an arc recti tying tube is a rectifier, the starting of which 5 can be controlled by a grid. After starting, the grid has no further control over the are, either to modulate, limit or extinguish it. When the tion will appear more fully as'lproceed with my specification.

In those forms of devices embodying the features of my invention shown in the accompanying drawlngs-- Figure 1 is a diagrammatic view of my im- 5 proved apparatus; and Figs. 2 and it are similar views showing modifications V In Fig. 1, the A, C. power supply is indicated by He, ill. M2 indicates the arc rectifying tube with the plate til grid Hi2 and cathode 2. This tube, as here shown, delivers impulses of unidirectional current or direct current to the line its containing. for example, the street lamps lit arranged inseries.

lac indicatesa pliotron tube withthe plate lat grid i563 and cathode are. The plate of" the tube E55 is connected by the Wire 85h to a" battery (15%, the other terminal of which is connected by the wire i533 to the grid it? of the tube H2. The cathode tell is connected by the 40 we "let to the cathode 652" of the tube iii 15% indicates'a grid transformer for supplying grid voltages to the grid are? of the tube 85!! from the line llll, ill. The secondary coil 555 I of the transformer has a mld-tap leading through the wire 55% to the grid itc One terminal oithis coil leads through the resistance llil to the cathode lit and the other terminal leads through the inductance i58 to the cathode I".

movements of the core I58 will change the relation between the inductance and resistance in the supply to the grid I50 which will split the phase 3 of the current delivered tothe grid I58. Variations in the load in the line I28 will tend to move the core I2I, causing the core I89 in the inductance I88 to be shifted to vary this inductance. The battery I52 is arranged to deliver a counter or non-starting voltage on the grid H2". The tube I50, however, is adapted to deliver a voltage during each half cycle which is suflicient to overcome the counter voltage of the battery I82 and impose a starting voltage on the grid 2*. The exact time in each half cycle, however, when the voltage delivered by the tube I58 overcomes the battery voltage is shifted by the extent of the 7 tion is illustrated in Fig. 2 where the A. C. line wires'are'indicated by 2l8, 2| l, the line by 228,

the lamps by 2 I 3, the coil in series with the lamps by 228 and the movable core therein by 22!.

The are rectifying tube is indicated by M2 and the same is provided with the plate 2m, grid M2 and cathode 212.

In the device here shown, the timing of the impulses on the grid ,2l2 is controlled by the ondary 255 supplies the grid H2". 288 indicates a variable inductance operated by a movable core 26!! connected to the lever 222.

In the operation of the device, any increase tendency of current in the line 228 causes the solenoid 220 to rock the lever'222 to move the movable plate 258* of the variable condenser 258. This Will change the capacity of the condenser to advance or retard the starting voltage in the primary 255 of the grid transformer. In this way, the timing of the starting voltages on the grid 2l2 may be shifted with respect to the alternations of potential on the lines 2"), 2.

In the form shown in Fig. 3, the A. C. power lines are indicated by 3), 3i i, the load line by 328, the lamps by 3l3, the arc rectifying tube by 8I2 with the plate ,3l2', the grid 3l2 and the cathode 3l2.

352 indicates a battery connected to the grid iil2 and to the line wire 3| i. In series with this battery is a resistance 388 and variable inductance 358. 320 indicates a solenoid in series with the line 328 containing the movable armature 3 connected by the lever 322 to a movable core 358 in the variable inductance 388. In this device the timing i accomplished by varying the inductance in the battery circuit The parts are so arranged, for exam le. that any tendency of the current in line 328 to increase will cause the plunger 32! to be pulled in further, which will operate on he plunger 358 to increase the inductance 358 in-proportion to the resistance 380 described embodiments of my invention the responsive element, such as the direct current solenoid, is actuated by the current flowing in the lamp or load circuit, and this responsive element is capable of immediately and instantly effecting a shift in the grid excitation of the :tube which is directly in series with the work circuit, where-. by the flow of current may be regulated substantially within the half-cycle. As a result, the

effective current flow in the work circuit may be 'kept constant with a high degree of accuracy and within a remarkably small tolerance or margin.

While I have shown and described certain embodiments of my invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made without departing from the spirit and scope of the invention as disclosed in the appended claims, in which it as my intention to claim all novelty inherent in my invention as broadly as permissible, in view of the prior art.

What I regard as new, and desire to secure by Letters Patent, is;

1. In combination, an alternatin current supply; a grid controlled are rectifying tube delivering direct current; a source of constant potential applied to the grid of said tube, a second grid controlled arc rectifying tube in the grid circuit of said first mentioned tube; a phase-splitting circuit supplying potentia to the grid of said second tube; and means whereby the relation of the constants of the phase-splitting circuit is altered to change the current flow through said second tube to overcome the bias on said first tube to control the direct current output of said tube throughout its full range.

2. A device of the character claimed in claim 1 wherein said means is contr lled by the amount of direct current delivered by said first tube.

3. In combination, an alternating current supply line, a normally closed direct current work circuit of variable resistance comprising a plurality of series connected incandescent lamps and a grid controlled tube conductively connected in series, said tube having a grid and a plate and being rendered conductive by excitation of its grid to conduct current during half cycles of the same polarity whereby the load circuit is traversed by direct current only, a grid excitation circuit, means energized from said supply line for applying grid potential to said excitation circuit synchronously with the application of alternating potential of one polarity to said plate, a solenoid connected in series in said work circuit 'having a core movable by current flow through said solenoid, spring means controlling the position of said core to counterbalance the pull thereupon for various positions thereof, and means comprising a variable inductance having a movable core mechanically connected to the core of iected.

HUGH E. YOUNG. 

